Two recent U.S. marketing campaigns have used social media to connect with a mass audience.
First came Philips Norelco Bodygroom with their shaveeverywhere.com campaign.
This jokey video as well as being hosted on its own domain was posted at youtube.com and at heavy.com and has allegedly been downloaded one billion times.
Now Gillette have launched a campaign, which parodies an online grassroots campaign in format. According to Advertising Age: “The Noscruf campaign includes paid search ads on Google and other search engines, promotional placement on Heavy.com and a posting on YouTube.com for two viral videos from a fictional advocacy group - National Organization of Social Crusaders Repulsed by Unshaven Faces - and its Web site, Noscruf.org.”

In this case the campaigners are women who want their menfolk to shave and have created the noscruf website as part of their campaign. The site (above) is being visited 60m times a day, say Ad Age, citing Alexa. It is the work of Digitas, a Boston-based agency.
What is intriguing about both of these campaigns is that:
1) they are online in inspiration and execution;
2) the off-line element is limited to PR - the Bodygroom campaign benefited from a plug on Howard Stern’s syndicated radio show;
3) they make use of existing places of debate and traffic - youtube.com and heavy.com and have not depended solely on destination urls.
Imaginative pieces of buzz marketing, both.